Fun, simple game. I got to ~5k points before it made me F (that you mercy cleared bullets around the player on switch helped me out a lot, kinda like bombing in a normal bullet hell). Pretty fun for a simple concept, the growing circle does work pretty well to increase the difficulty as time goes on. :)
Criticism wise, I feel it could have used a few different patterns, bullets were mostly random (or so I thought). With some extra colors and patterns it could look quite pretty! There could also be an additional risk part with a click in the control swap section also firing off extra bullet waves.
But well, just thoughts!